Hydraulic fracture composition and method

ABSTRACT

A method for improving hydraulic fracturing creates coated proppants containing one or more chemical constituents bonded to a substrate and introduced into the fracturing fluid itself. The substrate that eventually acts as a proppant may be sand, ceramic, resin coated sand, and other materials. Typically, the materials that are coated as powders adhered to the substrate may include friction reducers, biosides, oxygen scavengers, clay stabilizers, scale inhibitors, gelling agents, or the like. By adhering solid materials to a substrate  12  by a binder  14 , a single, solid, granular material may be maintained onsite, requiring reduced footprint, reduced mixing and may introduce almost instantaneously into a fracturing flow stream all the necessary chemical constituents, which will eventually become mixed. The result is reduced time, energy, manpower, equipment, and space at the sight, while reducing the environmental impact of transportation, spills, hydrocarbon use, and the like.

RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 13/299,288, filed Nov. 17, 2011, which is acontinuation-in-part of U.S. patent application Ser. No. 12/789,177,filed May 27, 2010, which is a continuation of U.S. patent applicationSer. No. 12/324,608, now U.S. Pat. No. 7,726,070, issued Jun. 1, 2010 toThrash, which claims the benefit of U.S. Provisional Patent ApplicationSer. No. 61/012,912, filed on Dec. 11, 2007.

BACKGROUND

1. The Field of the Invention

This invention relates to oil field and oil well development, and, moreparticularly, to novel systems and methods for fracturing and proppingfissures in oil-bearing formations to increase productivity.

2. The Background Art

Oil well development has over one hundred years of extensive engineeringand chemical improvements. Various methods for stimulating production ofwell bores associated with an oil reservoir have been developed. Forexample, United States Patent Application Publication US 2009/0065253 A1by Suarez-Rivera et al. and entitled “Method and System for IncreasingProduction of a Reservoir” is incorporated herein by reference in itsentirety and provides a description of fracturing technology in order toincrease permeability of reservoirs. Moreover, various techniques existto further improve the fracture channels, such as by acid etching asdescribed in U.S. Pat. No. 3,943,060, issued Mar. 9, 1976 to Martin etal., which is likewise incorporated herein by reference in its entirety.

In general, different types of processes require various treatments. Ingeneral, well production can be improved by fracturing formations.Fracturing is typically done by pumping a formation full of a fluid,containing a large fraction of water, and pressurizing that fluid inorder to apply large surface forces to parts of the formation. Theselarge surface forces cause stresses, and by virtue of the massive areasinvolved, can produce extremely high forces and stresses in the rockformations.

Accordingly, the rock formations tend to shatter, increasing porosity anproviding space for the production oil to pass through the formationtoward the bore hole for extraction. However, as the foregoingreferences describe, the chemistry is not simple, the energy and timerequired for incorporation of various materials into mixtures is time,money, energy, and other resource intensive.

It would be an advance in the art if such properties as viscosity,absorption, mixing, propping, and so forth could be improved by animproved composition and method for introduction.

Moreover, hydraulic fracturing has a rather sophisticated process foradding various constituents to the fracking fluids. Not only mustproppants be added, but various other chemicals. In certain fracturingprocesses, it has been found important or even necessary to blendmaterials into the working fluid for fracturing. Such blending requiressubstantial equipment, occupying a very significant footprint on theoverall well site.

Moreover, this equipment requires manpower, and maintenance of numerousreceiving and storage areas. These are needed for various constituentproducts that will ultimately be added to the working fluid. All ofthese processes for mixing auxiliary materials into the fluid causedelays in time, since many of the materials require substantial mixing.

Particularly with small particles, surface tension tends to float suchmaterials on the of liquids and require substantial mixing andsubstantial associated time. Many solids must be pre-mixed in oils,emulsions, and the like, increasing the effect of any spill. Meanwhile,addition of chemicals to a fracturing flow necessarily creates unevendistributions of additives. For example, upon addition, into the flow, aconstituent is at a very high concentration near the well head.Meanwhile, none of that newly added constituent exists elsewhere. Thus,the ability to thoroughly distribute material, or to even get itdistributed well throughout the fluid being introduced, has provendifficult.

Similarly, transportation of individual constituent chemicals andmaterials to the well site requires multiple vehicles specialized todifferent types of materials and phases. For example, some materials arefluids, some are solids, some use a water solvent, some use apetroleum-based solvent, and such materials must be hauled, delivered,and handled in distinct ways with their own suitable storage, handling,and transport equipment.

Various complaints have been encountered with the amount ofhydrocarbons, such as various emulsions, chemical additives, includingsuch materials as diesel fuel and the like that are often used. Withsuch liquid chemicals on site, the risk of surface contamination due tochemical spills of such materials is increased. Even when contained insmaller containers, such materials run the risk of spills, carryingabout by water, wind, and other weather, as well as the prospect ofpossible spilling during delivery, handling, or the feeding and mixingprocesses.

Meanwhile, the operational footprint required for storage, mixingsystems, receiving, shipping, and the like increase the overalloperational footprint of a well site. Moreover, money, labor, and timeare substantial for the process of receiving, preparation, storage,handling, and ultimately mixing materials that will be added to afracturing fluid.

Thus, it would be a substantial advance in the art to provide a systemand method, and particularly a material, that would eliminate many ofthe handling, equipment, footprint, transportation, and other problemsthat exist in prior art materials and mixing systems to service fracturefluids.

BRIEF SUMMARY OF THE INVENTION

In view of the foregoing, in accordance with the invention as embodiedand broadly described herein, a method, apparatus, and composition aredisclosed in certain embodiments in accordance with the presentinvention, as including a substrate that may be formed of sand, rockproduct, ceramic sand, gravel, or other hard and structurally strongmaterials, provided with a binder to temporarily or permanently secure ahydrating polymer in proximity to the substrated. When used herein anyreference to sand or proppant refers to any or all of these used inaccordance with the invention. In certain embodiments of a method inaccordance with the invention, a composition as described may be mixeddirectly into drilling fluids, such as a fracturing fluid made up ofwater and other additives.

By virtue of the increased surface area and weight provided to thepolymeric powders affixed to the substrate, the surface area, andconsequently the frictional drag, is greatly increased, sweeping thematerial of the invention into a flow of fluid. This greatly decreasesthe time required to absorb polymers into the fluid.

In fact, rather than having to wait to have the polymers thoroughlymixed, or absorb a full capacity of water, and thereby flow properlywith the drilling fluid or fracturing fluid, a composition in accordancewith the invention will sweep along with the fluid immediately, with theweight of the substrate submerging the polymer. Meanwhile, the crosssectional area presented results in hydrodynamic drag sweeps thecomposition along with the flow.

Meanwhile, over time, the polymeric powder adhered to the substrate willabsorb water, without the necessity for the time, energy, temperature,mixing, and so forth that might otherwise be required by surface mixing.Thus, the composition in accordance with the invention is immediatelytransportable and flows, relying on the drilling or fracturing fluid asits carrier.

Moreover, as the polymer tends to pick up more water, the density of thegranule of substrate and polymer powder becomes closer to the density ofwater. Accordingly, the size increase and the density change tend todrive the particles of the composition even more homogeneously with theflowing fluid. Thus, the sand does not settle out in various eddies,obstructions, and other locations of low velocity. Rather, the sandcontinues to be carried with the fluid, providing a double benefit. Thatis, the sand weight and area helps to initially mix and drive theparticles (granules) with the fluid. Thereafter, the hydration of thepolymer tends to increase the surface area and reduce the density of thegranule or particle, tending to make the particles flow even better andmore homogeneously with the surrounding fluid.

Ultimately, as the particles (granules) of the composition flow intofracture locations, they provide very small proppants as the substrate,such as sand, becomes trapped and lodged at various choke points.Nevertheless, because of the small size, the sand or other substrateacting as a proppant, simply needs to provide an offset, keepingfractured surfaces from collapsing back against one another. Byproviding the small, strong points of separation, the substrate providesa well distributed proppant, carried to maximum extent that the fluidswill travel, and deposited in various traps, choke points, and the like.

The net saving in time, money, energy for heating and pumping, and thelike is significant. Meanwhile, various technologies for reducingfriction in the flow of fluid pumped into bore holes and other formationspaces is described in several patents, including U.S. Pat. No.3,868,328, issued Feb. 25, 1975 to Boothe et al. and directed tofriction reducing compounds, as well as U.S. Pat. No. 3,768,565, issuedOct. 30, 1973 to Persinski et al. and directed to friction reducing,U.S. Patent Application Publication US 2001/0245114 A1 by Gupta et al.directed to well servicing fluid, and U.S. Patent ApplicationPublication US 2008/0064614 A1 by Ahrenst et al. and directed tofriction reduction fluids, all described various techniques, materials,methods, and apparatus for developing, implementing, and benefittingfrom various well fluids. All the foregoing patent applicationpublications and patents are hereby incorporated by reference.

Similarly, the development of various chemicals has been ubiquitous inoil field development. For example, U.S. Pat. No. 3,442,803, issued May6, 1969 to Hoover et al. is directed to thickened friction reducers,discusses various chemical compositions, and is also incorporated hereinby reference in its entirety.

In one embodiment of an apparatus, composition and method in accordancewith the invention, a method may be used for formation fracturing. Theformation may be in rock and within or near an oil reservoirunderground. One may select an oil field region having a formation to befractured. Fracturing may be sought to increase production. By providinga bore into the formation and a pump, a carrier material, typicallycomprising a liquid, and sometimes other materials dissolved or carriedtherein may be pumped into the formation through the bore.

The carrier as a liquid, or slurry comprising a liquid, or otherwisecontaining a liquid may be driven by the pump to be pressurized into theformation. However, the carrier may be provided an additive formed asgranules. Each granule may include a substrate, such as a grain of sand,ceramic sand, crushed rock, other rock products, or the like havingbonded thereto many particles (e.g., powder) formed from a polymer.

The polymer may be selected to have various properties, includinglubricity, water absorption, water solubility, or the like. Thishydrophilic polymer may be bonded permanently, temporarily, or the liketo secure to the substrate. Various binders may be used alone or incombination. These may range from a solvent (e.g., organic or water)simply softening the polymer itself to bond it, to glues, sugars,molasses, and various other saccharides, as well as other products,including starches, other polymers, and so forth.

Thus, with some bonds, the polymer powder may be less permanent orattached to have a bond that is less robust. Over time, the polymerpowder so attached may wear off, pull away, or otherwise remove from thesubstrate into the carrier fluid, and may even act as a viscous agent,lubricant, or the like in the carrier.

The method may include introducing the additive directly into thecarrier. The more dense substrate will immediately submerge the granulesin the carrier at ambient conditions. Thus heating, extensive mixing,waiting, and the like may be dispensed with, as the granules typicallywill not float or resist mixing once initial surface tension is broken.

Pumping the carrier toward the formation is possible immediately. Thecarrier fluid carries the granules by the liquid dragging against thesubstrate (with the particles of polymer attached. The substrate's crosssectional area engages immediately the surrounding liquid, dragging itinto the carrier to flow substantially immediately therewith.

Meanwhile, weighting, by the substrate of the polymer, permits thegranules to flow into and with the carrier independently from absorptionof any of the liquid into the polymer. Nevertheless, over time,absorbing by the polymer a portion of the liquid results in the polymerexpanding and providing by the polymer, lubricity to the carrier withrespect to the formation;

Creating fractures may be accomplished by pressurizing the carrier inthe formation. This creates fissures or fractures. Thus, flowing of thecarrier and particles throughout the fractures or fissures in theformation results in lodging, by the particles, within those fracturesor fissures. Unable to re-align, adjacent surfaces of rock, now fracturecannot close back together due to propping open the fractures by thesubstrate granules lodging in the fractures.

The substrate is best if selected from an inorganic material, such assand, ceramic sand, or other hard, strong, rock product. The polymer maybe selected from natural or synthetically formulated polymers. Forexample polymers of at acrylic acid, acrylate, and various amides areavailable. Polyacrylamide has been demonstrated suitable for allproperties discussed above.

In fracturing a rock formation, the method may include providing anadditive comprising a substrate formed as granules, each having anexterior surface, particles formed of a hydrophilic material, theparticles being comminuted to a size smaller than the size of thegranules and having first and second sides comprising surfaces. Thegranules may each be coated with the particles, the particles being dryand bonded to the exterior surface by any suitable binder, including thepolymer softened with a solvent. The particles are each secured by thefirst side to the granules, the second side extending radially outwardtherefrom.

Upon identifying a reservoir, typically far underground from thousandsof feet to miles, perhaps, and extending in a formation of rock, oneneeds to provide a bore into the formation. Providing a carrier,comprising a liquid, and possibly other materials known in the art, isfor the purpose of fracturing the formation. Introducing the additivedirectly into the liquid at ambient conditions is possible, because thesubstrate weighs the granules down, and there is no need for longmixing, heating or the like as in addition of polymers directly to thecarrier.

Thus, pumping may continue or begin immediately to move the carrier andadditive down the bore and toward the formation. This results inexposing the second sides of the polymer powder particles directly tothe liquid during transit of the carrier and additive toward and intothe formation. The polymer particles thus begin absorbing, a portion ofthe liquid, typically principally water. Swelling of the polymerincreases the size, effective diameter, and cross-sectional area, thusincreasing the fluid drag on the granules.

Fracturing, typically by hydraulic pressure in the carrier createsfissures in the formation by fracturing the rock pieces in bending, orby layer separation, with tensile stresses breaking the rock. Theresulting fissures allow carrying, by the carrier, of the granules intothe fissures. However, fissures vary in size and path, resulting inlodging of granules, within the fissures. The granules do not settle outfrom the carrier, and thus may travel far into the formation and everyfissure. However, each time a grain or granule is lodged like a chockstone, it obstructs the ability of the adjacent rock surfaces to closeback with one another.

Thus, rather than the proppant (substrate) settling out ineffectually,failing to prop open the fissures, the granules are swept forcefullywith the flow of the carrier wherever the carrier can flow, untillodged. Meanwhile, the lubricity of the polymer aids the granules, andthus the substrate from being slowed, trapped, or settled out by theslow flowing boundary layer at the solid wall bounding the flow.

In summary, weighting, by the substrate, sinks the polymer into thecarrier readily and independently from absorption of the liquid into thepolymer. Mixing, dissolving, and so forth are unnecessary, as thesubstrate drags the polymer into the carrier, and the carrier drags thegranule along with it in its flow path. Lubrication is provided by thepolymer between the substrate of each granule and adjacent solid wallsof the bore, passages previously existing in the formation, and thefissures formed by fracturing. Any separating, by some of the powderedpolymer particles from the substrate, still reduces friction drag onpassage of the carrier and particles within the formation.

A composition for fracturing and propping a formation of rock mayinclude a fluid operating as a carrier to be pumped into a rockformation, a substrate comprising granules of an inorganic material,each granule having an outer surface and a size characterized by amaximum dimension thereacross, and all the granules together having anaverage maximum dimension corresponding thereto. A polymer comprising ahydrophilic material selected to absorb water in an amount greater thanthe weight thereof may be bound to the substrate. The polymer iscomminuted to particles, each particle having a size characterized by amaximum dimension thereacross.

All the polymer particles may be characterized by an average maximumdimension, and an effective (e.g., hydraulic diameter). The averagemaximum dimension of the particles is best if smaller, preferably muchsmaller, than the average maximum dimension of the granules.

The particles of the polymer, bound to the substrate, will travel withit in the fluid. Particles of the polymer are thus further directlyexposed to water in the fluid during travel with the fluid. Thegranules, flowing in the fluid, are carried by the hydrodynamic drag ofthe fluid against the cross-sectional area of the granules coated withthe particles of the polymer. The polymer, selected to expand byabsorbing water directly from the fluid, increases the area and drag,assisting distribution in the formation by the carrier fluid. Thepolymer meanwhile operates as a lubricant lubricating the motion of thesubstrate against the formation during flow of the granules againstsolid surfaces in the formation, bore, and fracture fissures.

The inorganic material, such as sand, ceramic sand, or the like istypically sized to lodge in fissures formed in the formation and hasmechanical properties rendering it a proppant capable of holding openfissures formed in the formation. In certain embodiments, a watersoluble binder is used, then a substrate may release additives into thefracturing fluid quickly or slowly after insertion in the working fluid.

A substrate may perform as a proppant, and may be constituted of sand,ceramic, another rock or mineral product, a resin coated, or othermaterial used to prop open fractures. Such a substrate may be providedwith a binder securing powdered components of suitable additives to beintroduced into a fracturing fluid.

For example, a friction reducer, bioside, oxygen scavenger, claystabilizer, scale inhibitor, gelling agent, or the like may be includedin a mix, or as an element to be adhered to a substrate proppant. Thesubstrate thereby forms particles that will easily be drawn into a flowof fracturing fluid, thus introducing all the necessary constituentsinto the flow. This occurs rapidly, without having to wait for mixing tooccur topside on the site before introduction into the bore. Rather,mixing can take place and hydration or distribution in the flow may takeplace on the fly as the flow of fluid courses through the bore towardthe formation. Thus, the preparation and introduction time on thesurface at the well site is minimized.

In certain embodiments, the composition may be mixed directly into thefluid to form a complete and suitable fracturing fluid with all thenecessary additives desired. By adhering chemicals to the proppant asthe operable substrate, in the correct ratios, elaborate mixing ratiosand elaborate mixing processes, and control thereof, as well as theirrelated equipment, personnel, time, storage, and handling are greatlyreduced, and optimally eliminated. Thus, the operational footprint of aservice company on the well site is reduced, as well as the time, cost,labor, and so forth required to measure, add, mix, and otherwiseintroduce desired chemical constituents into the fracturing fluid.

By coating a proppant or substrate with the suitable materials (e.g.,chemicals, etc.) an even mix of chemicals is maintained within thefracturing fluid much more easily. Moreover, distribution thereof withinthe flow is straightforward. In fact, all those additives may therebyall be present in exactly the proper ratios at all times at the timethey are introduced. Thus, adding them one at a time, working with themto try to get them all introduced at about the same time, and so forth,as encountered in the prior art is no longer a problem.

Because many or all desired constituents may be coated onto a singlesubstrate 12, or each granule of a single substrate, then numerousconstituents, including previously dissolved liquids or solids that havebeen rendered liquid by introduction into solvents, in order to ensuremore rapid mixing, may be reduced or eliminated. Thus the full array ofconstituent chemicals to be used as additives in the fluid may beprovided with proppants in the delivery of a single material, granularin nature, solid in phase, and simple to be stored, transported,handled, and the like. Thus, emissions, spills, other environmentalrisks, may be reduced or eliminated.

By using powdered base chemicals, the carriers or solvents that werepreviously needed, often hydrocarbon based emulsions and the like, maybe eliminated. Thus, the risk of surface spills and consequentcontamination may be reduced or eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing features of the present invention will become more fullyapparent from the following description and appended claims, taken inconjunction with the accompanying drawings. Understanding that thesedrawings depict only typical embodiments of the invention and are,therefore, not to be considered limiting of its scope, the inventionwill be described with additional specificity and detail through use ofthe accompanying drawings in which:

FIG. 1 is a schematic cross-sectional view of a material including asubstrate provided with a binder securing a hydrating polymer thereto inaccordance with the invention;

FIG. 2 is a schematic block diagram of one embodiment of a process forformulating and producing fluid additive particles in accordance withthe invention;

FIG. 3 is a schematic diagram of the fluid-particle interaction in anapparatus, composition, and method in accordance with the invention;

FIG. 4 is a chart illustrating qualitatively the relationship betweenvolumetric increase over time at various temperatures, illustrating theimproved activation with minimum mixing and temperature increase ofparticles in accordance with the invention;

FIG. 5 is a schematic diagram illustrating one embodiment of frictionreducing by polymers used in compositions in accordance with theinvention;

FIG. 6A is a schematic diagram of the fracturing and proppant action ofparticles in accordance with a method and composition according to theinvention;

FIG. 6B is a schematic diagram illustrating a collection of proppantparticles positioning rock fragments in a formation away from oneanother in order to maintain open passages in the formation;

FIG. 7 is a schematic block diagram of a fracturing and propping processusing compositions and methods in accordance with the invention

FIG. 8 is a schematic diagram of processes illustrating alternativeoptions for coating, in which particles being adhered to the binderlayer may be added sequentially or simultaneously by species orconstituent particles;

FIG. 9 is a schematic diagram of an alternative coating process in whichmultiple binding layers are added over previous binding layers andlayers of particles; and

FIG. 10 is a schematic block diagram of some alternative coatingprocesses, including direct coating, sequentially adding particularconstituents, and sequentially adding binder and particulateconstituents to the particles.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

It will be readily understood that the components of the presentinvention, as generally described and illustrated in the drawingsherein, could be arranged and designed in a wide variety of differentconfigurations. Thus, the following more detailed description of theembodiments of the system and method of the present invention, asrepresented in the drawings, is not intended to limit the scope of theinvention, as claimed, but is merely representative of variousembodiments of the invention. The illustrated embodiments of theinvention will be best understood by reference to the drawings, whereinlike parts are designated by like numerals throughout.

Referring to FIG. 1, a material 10 in accordance with the invention mayinclude a substrate 12 formed of a suitable material for placement inthe vicinity of a fracture region. For example, a substrate may be aparticle of sand, ceramic sand, volcanic grit, or other hard material.In some embodiments, a substrate may be formed of organic or inorganicmaterial. Nevertheless, it has been found effective to use sand as asubstrate 12 inasmuch as it is submersible in water and will not floatas many organic materials will when dry. Likewise, the sand as substrate12 is comminuted to such a small size that interstices betweenindividual grains of the sand substrate 12 provide ample space andminimum distance for water to surround each of the substrate 12particles.

In the illustrated embodiment, a binder 14 may be distributed as acomparatively thin layer on the surface of the substrate 12. Typicalmaterials for binders may include both temporary and permanent binders14. Permanent binders include many polymers, natural and synthetic.Temporary binders may be sugar-based or other water soluble materials.For example, corn syrup, molasses, and the like may form temporarybinders. In the presence of water, such material may ultimatelydissolve. Nevetheless, so long as the substrate 12 is not turned, mixed,or otherwise disturbed significantly, any other materials supported bythe binder 14 would not be expected to dislocate.

Otherwise, certain naturally or synthetically occurring polymers mayalso be used as a binder 14. Lignicite may be used as a binder 14.Lignicite is a byproduct of wood, and provides material having goodadhesive properties, and substantial permanence as a binder 14 on asubstrate 12. Any suitable insoluble polymer may be used for morepermanent binding.

Other polymers may be used to form a binder 14. For example, variousmaterials used as glues, including mucilage, gelatin, other watersoluble polymers including, for example, Elmer's™ glue, and the like mayalso operate as binders 14 to bind materials to a substrate 12.

In certain embodiments, the substrate 12 may be used in oil fields as asubstrate 12 for polymer additives to fracture fluids. In othersituations, the substrate 12 may be implemented as a proppant.

Pigment 16 may be implemented in any of several manners. For example,the substrate 12 may have pigment 16 applied prior to the application ofthe binder 14. In alternative embodiments, the pigment 16 may actuallybe included in the binder 14, which becomes a pigmented coating on thesubstrate 12. In yet other embodiments, the pigments 16 may be added toa hydration particle 18 either as a pigment 16 mixed therein, or as apigment 16 applied as a coating thereto. Thus the location of thepigment 16 in the Figures is schematic and may take alternative locationor application method.

Particles 18 of a hydrophilic polymer material may be bonded to thesubstrate 12 by the binder 14. Particles may be sized to substantiallycoat or periodically coat the substrate 12.

In certain embodiments, the hydrophilic material 18 may be a powderedpolymeric material 18 such as polyacrylamide or any of the materials inthe patent documents incorporated by reference. In other embodiments,the particles 18 may actually be organic material having capillaryaction to readily absorb and hold water. In one presently contemplatedembodiment of an apparatus in accordance with the invention, theparticles 18 may be powdered polymeric material in a dehydrated state,and having a capacity to absorb water, typically many times the weight(e.g., five to forty times) of a particular particle 18.

The substrate 12, in certain embodiments, may be some form of sand orgrannular material. The sand will typically be cleaned and washed toremove dust and organic material that may inhibit the binder 14 frombeing effective. Likewise, the substrate 12 may be sized of any suitablesize. For example, sand particles may range from much less than amillimeter in effective diameter or distance thereacross toapproximately two millimeters across. Very coarse sands or ceramic sandsmay have even larger effective diameters. Hydraulic diameter iseffective diameter (four times the area divided by the wettedperimeter). However, in one presently contemplated embodiment, washedand dried sand such as is used in construction, such as in concrete, hasbeen found to be suitable. Fine sands such as masonry sands tend to besmaller, and also can function suitably in accordance with theinvention.

Accordingly, the distance across each powder particle 18 may be selectedto provide an effective coating of powdered particles 18 on thesubstrate 12. In one presently contemplated embodiment, the effectivediameter of the particles 18 may be from about a 30 mesh size to about a100 mesh size. For example, a sieve system for classifying particles hasvarious mesh sizes. A size of about 30 mesh, able to pass through a 30mesh sieve, (i.e., about 0.6 mm) has been found suitable. Likewise,powdering the particles 18 to a size sufficiently small to pass througha 100 mesh (i.e., about 0.015 mm) sieve is also satisfactory. A meshsize of from about 50 mesh to about 75 mesh is an appropriate materialto obtain excellent adhesion of particles 18 in the binder 14, with asuitable size of the particles 18 to absorb significant liquid at thesurface of the substrate 12.

As a practical matter, about half the volume of a container containing asubstrate 12 as particulate matter will be space, interstices betweenthe granules of the substrate 12. One advantage of using materials suchas sand as the substrate 12 is that a coating of the particles 18 mayprovide a substantial volume of water once the particles 18 are fullysaturated. By contrast, where the size of the particles 18 is too manyorders of magnitude smaller than the effective diameter or size of thesubstrate particles 12, less of the space between the substrateparticles 12 is effectively used for storing water. Thus, sand as asubstrate 12 coated by particles 18 of a hydrophilic material such as apolymer will provide substantial space between the substrate particles12 to hold water-laden particles 18.

The diameter of the particles 18, or the effective diameter thereof, istypically within about an order of magnitude (e.g., 10×) smaller thanthe effective diameter of the particles of the substrate 12. This orderof magnitude may be changed. For example, the order of magnitudedifference less than about 1 order of magnitude (i.e., 10×) may still beeffective. Similarly, an order of magnitude difference of 2 (i.e., 100×)may also function.

However, with particles 18 too much smaller than an order of magnitudesmaller than the effective diameter of the substrate 12, theinterstitial space may not be as effectively used. Likewise, with aneffective diameter of particles 18 near or larger than about 1 order ofmagnitude smaller than the size of the particles of the substrate 12,binding may be less effective and the particles 18 may interfere morewith the substrate itself as well as the flow of water through theinterstitial spaces needed in order to properly hydrate a material 10.

Referring to FIG. 2, an embodiment of a process for formulating thematerial 10 may involve cleaning 22 the material of the substrate 12.Likewise, the material of the substrate 12 may be dried 24 to make itmore effective in receiving a binder 14. The material of the substrate12 may then be blended 26.

One embodiment, a ribbon blender provides an effective mechanism toperform continuous blending as the binder 14 is added 28. Other types ofmixers, such as rotary mixers, and the like may be used. However, aribbon blender provides a blending 26 that is effective to distributebinder 14 as it is added 28.

For example, if an individual particle of the substrate 12 receives toomuch binder 14, and thus begins to agglomerate with other particles ofthe substrate 12, a ribbon binder will tend to separate the particles asa natural consequences of its shearing and drawing action duringblending 26.

As the binder 14 is added 28 to the mixture being blended 26, theindividual particles of the substrate 12 will be substantially evenlycoated. At this stage, the binder 14 may also be heated in order toreduce its viscosity and improve blending. Likewise, the material of thesubstrate 12 or the environment of the blending 26 may be heated inorder to improve the evenness of the distribution of the binder 14 onthe surfaces of the substrate 12 materials or particles 12.

Blending 26 of the binder 14 into the material of the substrate 12 iscomplete when coating is substantially even, and the texture of thematerial 10 has an ability to clump, yet is easily crumbled and brokeninto individual particles. At that point, addition 30 of the hydrophilicparticles 18 may be accomplished.

For example, adding 30 the particles 18 as a powder into the blending 26is a naturally stable process. Typically the particles 18 attach to thebinder 14 of the substrate 12 particles, thus removing from activitythat location. Accordingly, other particles 18 rather than agglomeratingwith their own type of material will continue to tumble in the blending26 until exposed to a suitable location of binder 14 of the substrate12. Thus, the adding 30 of the particles 18 or powder 18 of hydrophilicmaterial will tend to be a naturally stable process providing asubstantially even coating on all the particles of the substrate 12.

Just as marshmallows are dusted with corn starch, rendering them nolonger tacky with respect to one another, the material 10 formulated bythe process 20 are dusted with particles 18 and will pour freely.Accordingly, distribution 32 may be conducted in a variety of ways andmay include one or several processes. For example, distribution mayinclude marketing distribution from packaging after completion ofblending 26, shipping to distributers and retailers, and purchase andapplication by users.

An important part of distribution 32 is the deployment of the material10. In one embodiment of an apparatus and method in accordance with theinvention, the material 10 may be poured, as if it were simply sand 12or other substrate 12 alone. Since the powder 18 or particles 18 havesubstantially occupied the binder 14, the material 10 will not bind toitself, but will readily pour as the initial substrate material 12 will.

The material 10 may typically include from about 1 percent to about 20percent of a hydrophilic material 18 or particles 18. The particles 18may be formed of a naturally occurring material, such as a cellulose,gelatin, organic material, or the like.

In one embodiment, a synthetic gel, such as polyacrylamide may be usedfor the particles 18, in a ratio of from about 1 to about 20 percentparticles 18 compared to the weight of the substrate 12. In experiments,a range of from about 5 to about 10 percent has been found to be themost effective for the amount particles 18.

Sizes of particles 18 may range from about 20 mesh to smaller than 100mesh. Particles 18 of from about 50 to about 75 mesh have been foundmost effective.

The binder 14 may typically be in the range of from about in ¼ percentto about 3 percent of the weight of the substrate 12. A range of fromabout ¾ percent to about 1½ percent has been found to work best. Thatis, with a binder such as lignicite, ¼ of 1 percent has been found notto provide as reliable binding of particles 18 to the substrate 12.Meanwhile, a ratio of higher than about 3 percent by weight of binder 14to the amount of a substrate 12, such as sand, when using lignicite asthe binder 14, tends to provide too much agglomeration. The pouringability of the material 10 is inhibited as well as the blending 26, dueto agglomeration. Other binders also operate, including several smallermolecules that are water soluble. For example, glues, gelatins, sugars,molasses, and the like may be used as a binder 14. Insoluble binders arealso useful and more permanent.

One substantial advantage for the material 10 in accordance with thepresent invention is that the material remains flowable as a sand-likematerial 10 into the fluids to be used in oil field fracturing. Thus,handling and application is simple, and the ability of granular material10 to flow under and around small interstices of fractures provides fora very effective application.

Referring to FIG. 3, a formation 80 such as a reservoir area of an oilmay increase large and small flows 82 in passages 84 formed in the rock86 of the formation 80. Typically, the flow 82 represented by arrows 82indicating the development of flow at a faster speed in center of apassage 84, and the lower velocity near the wall 88 of the passage 84,illustrates the flow 82 of fluid in the passage 84.

In the illustrated embodiment, the granules 10 or large compositeparticles 10 or the materials 10 formed as a granulated material 10,having the substrate 12 in the center column with the polymer 18 adheredby a binder 12 on the outside thereof. This material 10 may be added toa flow 82 being pumped into a formation 80. Initially, a particle 10will have an effective diameter 90 a. In this condition, the particle 10of material 10 is largely dependant on the density of the substrate 12,which constitutes the majority of its volume. Eventually, over time,with exposure to the liquid 82 or flow 82 and the water of that flow 82,the polymer 18 will absorb water, increasing in its effective diameter90 b. Ultimately, the polymer 18 or the polymer powder 18 willeventually become fully hydrated, increasing many times its size, andbeginning to dominate the effective diameter 90 c or hydraulic diameter90 c of the particle 10.

Initially, the diameter 90 a reflects the comparatively smaller size andlarger density of the particle 10 dominated by the weigh of thesubstrate 12, such as sand, ceramic sand, or some other hard and strongmaterial. Ultimately, the diameter 90 a or effective diameter 90 a issufficient to provide fluid drag according to fluid dynamic equations,drawing the particle 10 into the flow 82.

Meanwhile, the increase in diameter 90 b and the ultimate effectivediameter 90 c result in reduction of the density of the particle 10 asthe polymer 18 absorbs more water, bringing the net density of theparticle 10 closer to the density of water. Accordingly, the particles10 flow with the water exactly in sync, so to speak, rather thansettling out as a bare substrate 12 would do.

For example, in areas where eddies in the flow occur, such as corners,crevices, walls, and the like, heavy materials having higher density,such as sand and the like, normally will tend to drift out of the flow,toward a wall 88, and ultimately will settle out. Instead, by virtue ofthe large “sail” presented by the larger diameter 90 c of a fullyhydrated polymer 18, each particle 10 stays with the flow 82 in passage84, providing much more effective transport.

Referring to FIG. 4, a chart 92 illustrates a volume axis 94representing the volume of a particle 10 or material 10 in accordancewith the invention. The volume axis 94 is displayed orthogonally withrespect to a time axis 96, representing the passage of time of theparticle 10 submerged in a carrier 82 or flow 82 of fluid 82. Typically,at different temperatures, illustrated by curves 98 a-98 e, with thetemperature associated with curve 98 a being the coldest and thetemperature associated with the curve 98 e being the hottest, one canvisualize how heat added to a fluid flow 82 tends to increase thechemical activity and thus the rate of absorption of water into apolymer 18.

In an apparatus and method in accordance with the invention, theparticles 10 may be added directly to a flow 82, without waiting for anysignificant time to absorb water into the polymer 18. Instead, thenormal flow 82 will draw the particles 10 along in a passage 84 whileexposing each individual particle 10 to surrounding fluid 82, thuspromoting maximum rates of exposure and increased rates of absorption.Accordingly, the volume 94 increases, representing an increase in theabsorption of water into the polymer 18.

In an apparatus and method in accordance with the invention, the curve98 a is suitable because the entire travel within the well bore, andwithin the formation 80 by the fluid 82 bearing the particles 10 ispermissible and available as absorption time. By contrast, prior artsystems rely on the increased temperature of curve 98 e in order toprovide the time, temperature, and mixing to work polymers into a flow82 or liquid carrier 82.

Referring to FIG. 5, in one embodiment of an apparatus, composition, andmethod in accordance with the invention, some of the polymer 18 mayeventually be scraped, sheared, or otherwise removed from the particles10. If bonded only by itself with a water solvent, such a separation maybe easier than if bonded by a more durable polymer. Such a release mayeven be engineered, timed, controlled by a solvent, or the like.

Thus, a certain amount of the polymer 18 may be released from thegranule 10 into the carrier fluid 82 to flow with the fluid 82 andoperate as a general friction reducer or provide its other inherentproperties to the carrier fluid 82. By an engineered process of bondingand un-bonding, the polymer powder may be less permanent or attached tohave a bond that is less robust. Over time, the polymer powder soattached may release, tear, wear off, pull away, or otherwise removefrom the substrate into the carrier fluid to act as a viscosity agent,surfactant, lubricant, or the like in the carrier, according to itsknown properties available for modifying the carrier 82.

For example, a polymer 100 or polymer chain 100 may be captured on acorner 102 defining a passage 84 into which a flow 82 will proceed.Accordingly, the corner 102 renders less of an orifice on the passage 84against entry of the flow 82 by virtue of the friction reduction of thepolymer 100 in the fluid, deposited temporarily or permanently about acorner 102. Thus, other particles 10 passing the corner 100 may shearoff a portion of the polymer 18 carried thereby or may rely on thepresence of the polymer 18 as a direct friction reducing agent on theparticle 10 (granule) itself, permitting the particles 10 to pass moreeasily with the flow 82 into the passage 84.

Referring to FIGS. 6A and 6B, various fracture processes are describedin various literature, including U.S. Patent Application publication US2009/0065253 by Suarez-Rivera et al. incorporated herein by reference.In a fracturing process, the pressure 110 or force 110 applied to aformation 80 tends to force apart large expanses of rock. As a result ofthat expansion of passages 84 in a rock formation 80, the rock isstressed. Pressure pumped into the fluid 82 flowing in the passages 84within the formation 80 results in bending stresses, tensile stresses,and so forth in the formation 80.

In FIG. 6A, the forces 110 illustrated the effect of a large pressureapplied over a large area. Since pressure multiplied by area equalsforce, applying an elevated hydraulic pressure to a large surface of arock 86 or rock segment 86 within a formation 80 results in tensileforces. Compressive forces will not tend to break rock. However, atensile force, which may be induced by bending, expansion, or the like,results in fracture of the rock. The fracture of the rock 86 thusresults in condition shown in the lower view, in which the passages 84are mere fissures within the rock 86.

The inset of FIG. 6A magnifies the fissures 84 or passages 84 formed inthe rock 86 and immediately entered by the working fluid 82 being usedfor the fracture. Having the particles 10 formed around substrates 12,the fluid 82 extends into each of the fissures formed. Fissures 84 aresimply passages 84. Some may be large, others small.

Referring to FIG. 6B, proppants 10 trapped in a small location stilldisplace a large amount of fractured rock 86. Thus, a small displacementat one location may still maintain opened another opening much largerelsewhere near the rock 86. The particles 10, even if as small as sand,may also collect and fill larger dead ends, slow flowing, and eddyingspaces, eliminating the ability for rocks 86 to return to formerpositions.

After fracturing rock 86 to form all of the fissures 84, the fluid 82will pass through the fissures, carrying particles 10, which eventuallycollect in cavities or reach choke points. In the absence of theparticles 10, fissures 84 could close back up after the fracturing waterleaves. However, by containing additives 18, and then losing them, theindividual substrates 12 are themselves rock in the form of sand,ceramic sand, or the like. Thus, a particle 10 or many particles 10 needonly obstruct the ability of the fissure 84 to close, and may “prop”open the fissures 84 precluding the rock 86 or the pieces of rock 86from settling back into alignment with one another.

Thus, the particles 10 both alone and in collected piles act asproppants left behind by the fluid flow 82, by virtue of the particles10 b captured. As a practical matter, it is the substrate 12 that actsas a proppant. The polymers 18 may eventually be worn off, or releasedby a water-soluble binder, but can easily be compressed, distorted, orcut. Regardless, as the fissures 84 open, they are back filled and closein at choke points and settling points collecting the substrate 12.

Continuing to refer to FIG. 6B, while referring generally to FIGS. 1-10,a formation 80 when fractured into individual pieces of stone 86, mayform various passages 84 or fissures 84 therein. To the extent thatproppant materials 10 lose the adhered particles 18 or powders 18, oncehydrated or mixed into the fluid 82, the substrate 12 is then in aposition to be deposited by eddies, slower flows, turning corners, andthe like. Thus, when the other materials 18 that have acted sails,drifting the substrate 12 with the fluid 82, have been removed, then thesubstrate 12 can more easily settle out. Accordingly, near corners, insmall crevices, in dead corners, and the like, the particles 10, largelystripped of their added constituent powders 18 (in whatever phase atthat point) may then drop out of the fluid 82 in a slow flow.

Once two portions of rock 86 separate from one another, forming apassage 84 of some size, a supply of proppant 10 b may then prevent thatrock portion 86 from moving back into its exact position, necessarilyforming passages 84 on virtually every side. Where a single particle 10of substrate 12 may drop out of the fluid 82 and collect, many more maylikewise collect. Accordingly, the various particles 10 b illustrated inFIG. 6B may collect, forming substantial support for various edges,corners, and the like of various rock 86. The result is that a smallmaterial, in comparatively small quantities, supporting an edge, or aparticular region of a rock 86 in the formation 80 may neverthelessmaintain a large network of passages 84 as a direct result.

In stone formations having stronger tensile strength, fractures mayproduce less debris to act as natural proppants. Nevertheless, inaddition to the particles 10 constituting primarily substrate material12 at this point, the passages 84 may be maintained open as is theobjective with fracturing.

Referring to FIG. 7, a process 111 may include preparing 112 a fluid 82.Processing 114 other additives other than the particles 10 may be doneaccording to any suitable methods, including prior art processes. Adding116 directly to the fluid 82, the particles 10 as described hereinabove,may be done in such a manner that the operators need not wait forabsorption or any other processes to take place. Additional energy forelevating temperature is not required, neither mixing or the like, otherthan adding 116 directly particles 10 in to the flow 82. The flow 82will immediately grab the particles 10 according the principles of fluiddynamics in which fluid drag is dependent upon a shape factor of theparticle 10, the density of the fluid 82, the square of velocity of thefluid, and so forth, as defined in engineering fluid mechanics

The fluid 82 now bearing the particles 10 would be immediately pumped118 into the formation 80 that is the reservoir 80 of an oil field.Eventually, pressurizing 120 the reservoir by pressurizing the fluid 82results in creating 122 fractures 84 or fissures 84 within the formation80 by breaking up the rock 86 of the formation 80. A fracture 84 withenough displacement may make a site for material 10 to stagnate andcollect.

Creating 122 fracture lines throughout the formation 80 is followed bypenetrating 124, by the particles 10 borne in the fluid 82 into thepassages 84 or fissures 84 in the rock 86 of the formation 80. Wheneverthe flow 82 of fluid 82 carries a particle 10 to a choke point 108 in apassage 84, as illustrated in FIG. 6, a particle 10 will be lodged asillustrated in the inset of FIG. 6, a particle 10 with its polymer 18still secured and intact may be lodged. Similarly, the substrate 12 maybe lodged 126 and the polymer 18 may stripped therefrom by theconsequent or subsequent flowing of material in the flow 82. Likewise,piles of stagnant particles 10 may backfill spaces, precluding rock 86settling back in.

After the lodging 126 or propping 126 of the fissures 84 by thesubstrate 12, in the particles 10, the passages 84 will remain open.These fissures 84 may then be used tolater withdraw 128 the fluid 82from the formation 80. Thereafter, returning 130 the formation 80 toproduction may occur in any manner suitable. For example, heat may beadded to the formation, liquid may be run through the formation as adriver to push petroleum out, or the like.

Referring to FIGS. 8-10, while continuing to refer generally to FIGS.1-10, in various alternative embodiments, multiple constituents may beused as the particles 18 or powder 18 held by the binder 14 to thesubstrate 12. For example, in various alternative embodiments, one ormore other constituents may be added in addition to friction reducers.In the embodiments described hereinabove, the polymeric powders 18 addedto the substrate 12 by the tacky or otherwise adhering binder material14 operated partly as a friction reducer but also as a sill encouragingdrifting of the particles 10 with the flow of the fluid 82 or flow 82 inthe fracture fluid 82. Thus, hydrophillic powder 18 served multiplepurposes.

Meanwhile, as described hereinabove, such polymers may be bonded to theouter surface of the binder 14, thus rendering themselves moresusceptible to absorbing water and being stripped of by friction againstthe walls 88 of various passages 84 in the formation 80. Accordingly,such materials may typically be used in combination with others invarious fractures. It has been found effective to include a frictionreducing material at a fraction of about 0 to about 10 percent of thetotal coating granules 18 or powder 18 adhered to the binder 14.

Similarly, biological organisms can change the pH in the water 82 orfluid 82 used for the fracture process. Accordingly, biocides orbacteriacides may eliminate the bacteria or reduce its population inorder to avoid changes in the mechanical properties of the fluid 82 aswell as changing the pH and thereby the corrosiveness of the fluid 82.

In the contemplated embodiment, such materials such as sodiumhypochlorite as a powder or crystal form may be used as one of theconstituents for the powder 18 to be bound by the binder 14. Likewise,chlorine dioxide may also be applied by a powder formed of a crystal andform thereof. Other biocides that may be included may be gouteraldehydeas a liquid, or as the constituents thereof in solid form. Similarly,quaternary ammonium chloride may be provided as a solid and therefore asa powder, or as a liquid.

Liquids may be included in the binder 14. Alternatively, the liquidconstituents may instead be separated from (or not dissolved in) theirsolvents in order to provide powders 18 for adhering to the particles10. Thus, the foregoing liquids as well as tetrakishydroxhydroxymethyl-phosphonium sulfate may be similarly treated.

As one or even as the only constituent, a particular material may beused as powder 18 adhered to the substrate 12 as part of a particle 10.Any one or more may be combined appropriately. Biocides, typicallyappear to be suitable in the range of from about 0 to about 3 percent ofthe particles 18 or powder 18 secured to the substrate 12.

Oxygen scavengers also assist in changing pH as well as preventingcorrosion, by removing available oxygen from the fluid 82. Removal ofoxygen prevents oxidation, commonly known as rust or corrosion. Thus,the liners, drilling equipment, and other tubular materials may increasetheir life and reliability and overall integrity of the well by reducingoxygen in the fluid 82. Accordingly, from about 0 to about 3 percent ofan oxygen scavenger may be included as part of the coating 18 or thepowder 18 adhered to each substrate 12.

Similarly, a clay stabilizer may be included in a proportion of fromabout 0 to about 3 percent of the coating 18. Thus, clay stabilizersthat are used in the fluid 82 may be modified or restricted fromswelling or shifting. For example, choline chloride as well astetramethyl ammonium chloride as well as sodium chloride (salt) may allbe provided as powders 18 to be bonded to the substrate 12 by a binder14.

Likewise, scaling inhibitors may be included at a rate of from about 0to about 3 percent of the powder 18 adhered to the substrate 12 or ofthe total weight of the product. Scaling involves the deposition onvarious conduits and walls, typically in pipes of various minerals, suchas carbonates. Changes in pH, changes in temperature, changes in variousconcentrations of other materials including that of the scaling materialmay cause scale to accumulate. Accordingly, scale inhibitors may beadded as particles 18 in an overall mix, or as part of another coatingprocess.

For example, various copolymers of acrylamides as well as sodiumacrylate are scale inhibitors that may be secured to the substrate 12 bythe binder 14. Similarly, sodium polycarboxylate and phosphonic acidsalt may all be provided in a solid form. All may be comminuted to apowder 18, and sieved to a common size corresponding to that of othermaterials. Accordingly, mixed in a proper ratio, the powders 18 mayactually be compositions of numerous constituents in suitableproportions.

Likewise, a gelling agent may be added in a proportion of from about 0to about 10 percent as a powder 18 secured to the substrate 12 ofparticle 10. A function of gelling agents is to alter viscosity. Thisimproves suspension of proppants, such as the substrate 12, sand, or thelike, in water. Typically, the speed or velocity with which gravity orother effects may drift a heavy substrate 12 or particle 10 out ofsolution to leave it elsewhere, is controlled to a large extent by therelative viscosity of the liquid fluid 82 through which the particles 10are passing. Accordingly, increasing the viscosity tends to keep theparticles 10 entrained and more evenly distributed within the fluid 82.

Accordingly, various gelling agents, or a single gelling agent selectionmay be used as a constituent forming the powder 18 adhered to asubstrate 12. Typical processes describe hearinabove and hereinafterillustrate that solid particles may be inducted into the flow 82 or thefluid 82 almost instantly when introduced as the particulates 10. Thus,rather than floating on top during extensive mixing, such materials maybe drawn quickly as part of the particles 10 discharged into the fluid82 at the well head.

Various experiments have shown the utility and ability to add many ofthese materials. Generally, anything that can be maintained stable for asuitable period of time may be added as powder 18 to a suitable binder14 holding it to a substrate 12. Thus, various hydrophilic polymers,including polyacrylamides and polyacrylates may be added. Guar gum,various guar derivatives, polysaccharide blends all have the mechanicalproperties to be suitable as constituents of the powder 18 of particles10.

Referring to FIG. 8, in one embodiment of a process in accordance withthe invention, a substrate 12 may have added to it a layer of binder 14.To the binder 14 may be added a particular powder 18 a or additive 18 ain solid form to be bound to the substrate 12 by the binder 14. In thisparticular embodiment, the powder 18 a is added first, in a particularfraction. Thereafter, various other constituents may be added in seriesas the powders 18 b, 18 c, 18 d, illustrated by differing shapes ofparticles. For example, the particles or powder 18 a is illustrated byan irregular shape, the powder 18 b by a rectangular shape, 18 c by adiamond shape, and 18 d by a circular shape. These shapes are merelyschematic in order to show the addition of various materials.

Continuing to refer to FIG. 8, the process may also operate by a methodof first mixing each of the different powders 18, including up to about10 or more. Typically, additives in the range of from about 5 to about 9different constituents may be comminuted and sieved (sorted) in order tomaintain all at approximately the same range of sizes.

In this way, by grinding to powder (comminuting) and then sorting with asieve, the various constituent materials may then be treatedmechanically as generic materials, mechanically equivalent. Thus, allmay be mixed together.

An important feature here is to avoid disparate sizes, and particularlythe inclusions of too many fines. Ultra fine particles tend to provideless included volume in each powder particle, and thus occupy moresurface area of the available binder 14 and the surface area of thesubstrate 12, thus inhibiting even coating and the addition of otherconstituents. Thus, in such an embodiment, the powder particles 18 a, 18b, 18 c, 18 d, and so forth may all be mixed in the exact proportiondesired, usually as a fraction or percentage of the total weight ofparticles 10, and each may then be included in a mixed supply (e.g.,bin, etc.) having the proportions desired, of each and everyconstituent. Thus, the process described with respect to FIGS. 1 and 2hereinabove may be used directly, with the powder 18 simply being a mixof other individual constituent chemicals as powders. Thus, allconstituents may be added “in parallel,” simultaneously.

Referring to FIG. 9, in an alternative embodiment, the substrate 12 mayhave added to it a binder 14, after which a layer of particles 18 may beadded to the binder. Following this, an additional layer of binder 14may be added to which additional particles 18 may be adhered.

In this embodiment, the additional layers of binder 14 and particles 18may provide sequential de-layering of the various powders 18 during theprocess of flowing through the bore and into the formation 80.Nevertheless, it has been found that adhering a supply of particles 18or powder 18 to a single layer of binder 14, provides adequate surfacearea, adequate binding, and sufficient area to hold a wide variety ofconstituent chemicals all adhered in a single coating process.

Referring to FIG. 10, while continuing to refer generally to FIGS. 1-10,one embodiment of a process 20 may be illustrated with the cleaning 22,drying 24, and blending 26 as described hereinabove. Meanwhile, adecision 132 determines the mode of coating. For example, if thedecision is to coat directly, then preparing 134 sieved constituents mayinclude comminuting and sorting constituents, each sieved or otherwisesorted in order to provide a consistent size range for each.

Following the preparation 134 of the constituents, mixing 136 is neededfor the constituents in the suitable ratios or percentages. Thisprovides a single mixture of powdered particulates 18 suitable forbonding to a substrate 12. Applying 138 a binder is followed by applying140 the powder 18 to the binder 14 in coating the substrate 12 asdescribed hereinabove.

Following preparation of the of the granular particulates 10,postprocessing may include bagging, may include additional drying, ormay include protection against elements to which the material 10 will beexposed.

Post processing 142 may be followed by distribution 144 to variousdestinations. Distribution 144 may include, or may be followed up bystocking the distributed 144 product 10 at various sites for use.Ultimately, injecting 148 the granular material 10 into the fluid 82 forfracturing may complete the preparation and use of the product 10 inaccordance with the invention. Thereafter, the processes described withrespect to FIGS. 3-6B occur as a consequence of the configuration of thegranular material 10.

In certain alternative embodiments, as illustrated in FIGS. 8 and 9, themode decision 132 may involve adding powder 18 in series. For example,adding 150 a binder may be followed by adding 152 a powder species.Thereafter, a decision 154 may determine whether to add another species.If the decision is affirmative, then additional species may be added 152until the coating is completed. Thereafter, when no other additions areto be made, according to the decision step 154, then postprocessing 142continues, and the process 20 continues to ejection 148.

Similarly, the process of FIG. 9 illustrates the process in which adding160 a binder 14 is followed by adding 162 a powder constituent, afterwhich a decision 164 results in adding 160 more binder before adding 162more of a powder constituent. Thus, adding 152 powder only, compared toadding 168 binder 14 and adding 162 additional powdered constituents 18,reflect certain of the embodiments such as FIG. 9. Nevertheless, theembodiment of preparing 134 sieved constituents, through the applying140 the powder 18 as a mixture, is also illustrated in FIG. 8, orrepresented thereby, as described hereinabove.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrative,and not restrictive. The scope of the invention is, therefore, indicatedby the appended claims, rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

1. A method of augmenting a fracturing fluid, the method comprising:providing a fluid; providing a substrate, constituted as particles, eachdiscrete; providing a binder; providing a at least one firstcomposition, containing a polymer, characterized by a chemistry, andformed as a powder; coating the particles individually with the binder;forming granules by coating the binder of the particles individuallywith the powder; distributing the first composition in the fluid byintroducing the granules into the fluid.
 2. The method of claim 1,wherein the fluid is moving as a carrier, characterized by a viscosity,and the polymer selected to increase in size by absorbing the fluid. 3.The method of claim 3, wherein the polymer expands the effectivediameter of granules by absorbing the fluid. one
 4. The method of claim3, wherein the substrate has a first density and the powder has a seconddensity, the first density being greater than the second density.
 5. Themethod of claim 4, wherein the first and second densities are selected,and the size of the granules is selected to effect sinking the polymer,by the substrate, into the fluid.
 6. The method of claim 5, wherein theabsorption rate and amount of the fluid by the polymer are selected tobe effective to increase drag by the fluid acting on the granules. 7.The method of claim 6, wherein the absorption of the fluid by thepolymer is effective to distribute the granules throughout thecross-section of flow of the fluid.
 8. The method of claim 7, whereinthe at least one composition comprises a plurality of polymers, distinctfrom one another.
 9. The method of claim 8, wherein each polymer of theplurality of polymers is comminuted to a size range common to theplurality of polymers.
 10. The method of claim 9, wherein the pluralityof polymers comprises at least two polymers selected from: a frictionreducer; a biocide; an oxygen scavenger; a clay stabilizer; a scaleinhibitor; and a gelling agent.
 11. The method of claim 10, wherein thesubstrate is a proppant selected from sand, a ceramic, a rock product,and another manufactured, granular material.
 12. The method of claim 11,wherein: the friction reducer is selected from acrylamides; and theoxygen scavenger includes at least one of an ammonium and a sulfurcompound.
 13. The method of claim 11, wherein: the biocide is selectedfrom sodium hypochlorite, chlorine dioxide, gluteraldehyde, quaternaryammonium chloride, tetrakis hydroxymethyl-phosphonium sulfate, and acombination of at least two thereof; and the clay stabilizer is selectedfrom choline chloride, tetramethyl ammonium chloride, sodium chloride,and a combination of at least two thereof.
 14. The method of claim 11,wherein: the scale inhibitor is selected from an acrylamide, aco-polymer, sodium acrylate, sodium polycarboxylate, phosphonic acidsalt, and a combination of at least two thereof; and the gelling agentis selected from a polyacrylamide, a polyacrylate, guar gum, a guarderivative, a polysaccharide, a blend of polysaccharides, anotherhydrophilic polymer, and a combination of at least two thereof.
 15. Themethod of claim 1, wherein the binder is water soluble.
 16. The methodof claim 16, wherein the binder is formed of a thickness of coating onthe substrate and of a chemistry selected to dissolve during transportof the granules down the bore toward the formation.
 17. A method ofintroducing a proppant into a formation, the method comprising:providing a substrate, constituted as particles, each discrete;providing a binder; providing a at least one first composition,containing a polymer, characterized by a chemistry, and formed as apowder; coating the particles individually with the binder; forminggranules by coating the binder of the particles individually with thepowder; and distributing the first composition in the fluid byintroducing directly the granules into the fluid, and dissolving atleast one of the binder and the powder into the fluid.
 18. The method ofclaim 18, further comprising: dropping out of the flow of the fluid bythe substrate as a result of the binder releasing the polymer inresponse to at least one of dissolving of the binder, dissolving of thepowder, and shearing of the powder from the substrate.
 19. A method forintroducing a proppant and at least one chemical simultaneously into afracturing fluid, the method comprising: providing a fluid characterizedby a viscosity; providing a substrate, constituted as particles, eachdiscrete; providing a binder; providing a at least one firstcomposition, containing a polymer, characterized by a chemistry, formedas a powder, and comprising a molecule selected to increase in size byabsorbing the fluid; coating the particles individually with the binder;forming granules by coating the binder of the particles individuallywith the powder; distributing the first composition in the fluid byintroducing the granules into the fluid. the substrate and at least onefirst composition, wherein the substrate has a first density and thepowder has a second density, the first density being greater than thesecond density and selected to effect sinking the polymer, by thesubstrate, into the fluid immediately upon introduction thereinto, andthe absorption rate of the polymer is effective distribute the granulesby increasing drag of the fluid acting on the granules by swelling theeffective size thereof; providing the at least one composition, furthercomprising at least one of a friction reducer, biocide, oxygenscavenger, clay stabilizer, scale inhibitor, and gelling agent;providing the substrate, further comprising selecting a size thereof tobe effective to act as a proppant, the substrate being further formed ofmaterial selected from sand, rock, ceramic, a resin-coated inorganicmaterial, and another manufactured product; introducing the granulesinto the fluid directly; and sinking of the granules into the fluidunder the influence of gravity.
 20. The method of claim 19, furthercomprising constituting the powder from a plurality of materialsincluding at least one of: selecting a friction reducer fromacrylamides; selecting an oxygen scavenger from at least one of anammonium and a sulfur compound; selecting a biocide from sodiumhypochlorite, chlorine dioxide, gluteraldehyde, quaternary ammoniumchloride, tetrakis hydroxymethyl-phosphonium sulfate, and a combinationof at least two thereof; selecting a clay stabilizer from cholinechloride, tetramethyl ammonium chloride, sodium chloride, and acombination of at least two thereof; selecting a scale inhibitor from anacrylamide, a co-polymer, sodium acrylate, sodium polycarboxylate,phosphonic acid salt, and a combination of at least two thereof; andselecting a gelling agent from a polyacrylamide, a polyacrylate, guargum, a guar derivative, a polysaccharide, a blend of polysaccharides,another hydrophilic polymer, and a combination of at least two thereof.